slip to landing and speed

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AnnaG

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AnnaG
Hi all, I'm right at the end of my training for my PPL, in check-ride prep mode, and have a persistent problem that I know I'll figure out (because I'll keep practicing) but also wanted to ask for any thoughts you might have :)

Whenever I do a slip to landing, I pick up speed such that I usually can't land "on the numbers" or wherever it is that I'm aiming to land. It seems that a controlled approach goes quickly from controlled to a bit of chaos at the end.

How do I slip and manage speed in the transition from slip to final stable approach and flare?

Thanks for any and all opinions!
 
You might go to altitude with your instructor and do a series of slips, both L&R. Practice holding a steady 1.3 Vso airspeed. After a few it will become old hat.
 
Have your instructor demonstrate a good speed controlled slip and practice until you have it, the forward slip, and descending slipping turn are important tools to have at your disposal.

Be advised however your airspeed indicator is not correct while in the slip, usually reads low, you will notice an increase in indicated airspeed when you resume coordinated flight.

'Gimp
 
Have you been given instruction from a CFI on the proper way to slip. Keep practicing the slip at altitude,it will come to you.
 
AnnaG said:
Hi all, I'm right at the end of my training for my PPL, in check-ride prep mode, and have a persistent problem that I know I'll figure out (because I'll keep practicing) but also wanted to ask for any thoughts you might have :)

Whenever I do a slip to landing, I pick up speed such that I usually can't land "on the numbers" or wherever it is that I'm aiming to land. It seems that a controlled approach goes quickly from controlled to a bit of chaos at the end.

How do I slip and manage speed in the transition from slip to final stable approach and flare?

Thanks for any and all opinions!
Click to expand...


Well, if you are picking up too much speed, you aren't using enough rudder and are pushing the nose down too hard.

There is a better option to slipping to steepening your descent, and that is slowing down. Pull the throttle and trim up then pull for a chirpy stall warning, you'll drop quite precipitously, then as you approach your desired glide slope ease the nose back down for 1.2-1.3 Vso and add throttle to keep from sinking below your glide slope.

Landing energy is much easier to manage from the bottom side than the top.

If you are consistently finding you need to slip on final, you need to slow down overall. Go up and find your real 'landing stall' (Power Off, Dirty) stall speed at your typical dual and solo flying weights. Go to the IAS-CAS chart in the plane's manual, convert to CAS, multiply by 1.1, 1.2, 1.3, and 1.5. Now convert those numbers back to IAS. Now you have your real target speeds for the pattern. You want to enter downwind or achieve before base the 1.5, slow to 1.3 on the base-final transition then through adding the last of the flaps slow to the 1.1 as you cross the threshold. You use trim and pitch to manage your speed and throttle to control your slope/rate of descent. If you are trimmed correctly you'll find that it is very easy to maintain your airspeed as you make power changes to change rate of descent because the plane when trimmed correctly seeks to maintain that speed. You may want to practice the descent, configurations, and trim flicks, to make a smooth deceleration out in the practice area trying to maintain a steady 500-600fpm rate of descent.
 
Dear pilots, thank you, all. I think, from reading your replies, that I am not being assertive enough with trim, turning base to final too fast (downwind is usually stable), and then needing to slip, or slipping too fast without adequate control pressures. Can't wait to go back out and practice at altitude and in the pattern.
 
By the way welcome to the forum.
 
As pointed out if you have the thing trimmed right for the approach speed, slipping should not gain speed unless you're pushing forward. Don't do that.
However, if you are overshooting your landing point even in the slip you're either carrying power (why?) or not slipping hard enough or you're just got too high expectations.
 
Slips work better slow, too.

Henning, she isn't needing to slip. It's in the PTS and she's practicing it.
 
MAKG1 said:
Slips work better slow, too.

Henning, she isn't needing to slip. It's in the PTS and she's practicing it.
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Read her second post. The tell was the 'persistent problem'. It's not a persistent problem if you don't do them a bunch, and if you don't need them, you don't do them a bunch.;) The most persistent reason for needing slips is failure to trim for the correct, slower speed and trying to muscle it.

Slowing works excellent, passengers never notice you were hot and high, no drama involved at all. People in the back seat don't usually appreciate slips.
 
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Henning said:
Read her second post. The tell was the 'persistent problem'. It's not a persistent problem if you don't do them a bunch, and if you don't need them, you don't do them a bunch.;) The most persistent reason for needing slips is failure to trim for the correct, slower speed and trying to muscle it.

Slowing works excellent, passengers never notice you were hot and high, no drama involved at all. People in the back seat don't usually appreciate slips.
Click to expand...

Ok, but she still has to do it on her Checkride.
 
Henning said:
Well, if you are picking up too much speed, you aren't using enough rudder and are pushing the nose down too hard.

There is a better option to slipping to steepening your descent, and that is slowing down. Pull the throttle and trim up then pull for a chirpy stall warning, you'll drop quite precipitously, then as you approach your desired glide slope ease the nose back down for 1.2-1.3 Vso and add throttle to keep from sinking below your glide slope.

Landing energy is much easier to manage from the bottom side than the top.

If you are consistently finding you need to slip on final, you need to slow down overall. Go up and find your real 'landing stall' (Power Off, Dirty) stall speed at your typical dual and solo flying weights. Go to the IAS-CAS chart in the plane's manual, convert to CAS, multiply by 1.1, 1.2, 1.3, and 1.5. Now convert those numbers back to IAS. Now you have your real target speeds for the pattern. You want to enter downwind or achieve before base the 1.5, slow to 1.3 on the base-final transition then through adding the last of the flaps slow to the 1.1 as you cross the threshold. You use trim and pitch to manage your speed and throttle to control your slope/rate of descent. If you are trimmed correctly you'll find that it is very easy to maintain your airspeed as you make power changes to change rate of descent because the plane when trimmed correctly seeks to maintain that speed. You may want to practice the descent, configurations, and trim flicks, to make a smooth deceleration out in the practice area trying to maintain a steady 500-600fpm rate of descent.
Click to expand...

Henning I think the advice is misguided and could earn a checkride bust. DPEs want to see stable finals not chirping stall horns. After the ticket is earned, then practice lower edge of envelope stuff, but please do not do so at <pattern altitude. That's asking for a smoking hole in the ground from the weekend flyer; proficient pilot who flies often different story, different advice.
 
AnnaG said:
Hi all, I'm right at the end of my training for my PPL, in check-ride prep mode, and have a persistent problem that I know I'll figure out (because I'll keep practicing) but also wanted to ask for any thoughts you might have :)

Whenever I do a slip to landing, I pick up speed such that I usually can't land "on the numbers" or wherever it is that I'm aiming to land. It seems that a controlled approach goes quickly from controlled to a bit of chaos at the end.

How do I slip and manage speed in the transition from slip to final stable approach and flare?

Thanks for any and all opinions!
Click to expand...

You need to push on the rudder and push the stick/yoke hard opposite all the way. You will descend and slow at the same time. Once over the threshold release both at the same time and straiten the nose for landing.

If you are gaining or not reducing speed you are only doing it half-way. The nose should be radically off to one side and the opposite wing tilted toward the ground.
 
I'm flying a C152.

From what (else) I've read this morning, my problem occurs during short-field landing practice. Speed is definitely the issue, or rather, too much speed. If I slow to 1500-1700 RPMs abeam the numbers, then control speed, with trim, to 70 on base, and 55-60 on final, I might be okay. No need to slip.

But yes, I do need to slip for my check-ride and think that if I enter a slip with a slower, stabilized approach, and full rudder, I might see an improvement. I'm close, by the way, just not perfect : )

Thanks, again
 
Forward slip to side slip to forward slip is a good skill to learn.
 
There's no point in slipping with power in. Bring it to idle before the slip.
 
AnnaG said:
I'm flying a C152.

From what (else) I've read this morning, my problem occurs during short-field landing practice. Speed is definitely the issue, or rather, too much speed. If I slow to 1500-1700 RPMs abeam the numbers, then control speed, with trim, to 70 on base, and 55-60 on final, I might be okay. No need to slip.

But yes, I do need to slip for my check-ride and think that if I enter a slip with a slower, stabilized approach, and full rudder, I might see an improvement. I'm close, by the way, just not perfect : )

Thanks, again
Click to expand...

Slip to landing is a separate maneuver not necessary for short field landings. It's mainly for xwind and for clearing obstacles close to the runway that leave you too high to get down quickly enough just nosing and diving.

Short field is for what it says, short fields (runways or grass). The idea is to make an approach and a landing ON THE NUMBERS. That is, where you NEED to touch down. The trick is to either use max flaps and lower approach speeds. Or use standard landing config and flaps and reduce speed enough to pull the nose and touch down using the wings as a brake. Usually these landings are a little harder than usual.

If you choose max flaps, you will find yourself almost hovering over the threshold before touch down. If you use standard flaps, you must have the skill to avoid stalling and using those wings to brake you at the exact right moment.
 
CTLSi said:
Slip to landing is a separate maneuver not necessary for short field landings. It's mainly for xwind and for clearing obstacles close to the runway that leave you too high to get down quickly enough just nosing and diving.

Short field is for what it says, short fields (runways or grass). The idea is to make an approach and a landing ON THE NUMBERS. That is, where you NEED to touch down. The trick is to either use max flaps and lower approach speeds. Or use standard landing config and flaps and reduce speed enough to pull the nose and touch down using the wings as a brake. Usually these landings are a little harder than usual.

If you choose max flaps, you will find yourself almost hovering over the threshold before touch down. If you use standard flaps, you must have the skill to avoid stalling and using those wings to brake you at the exact right moment.
Click to expand...

However in real life short fields tend to be short due to trees, mountains and the like, combining full flaps with a slip is a great way to drop into a short field and touch down without using up what little real estate you have.


Also some planes don't have flaps :yes:

Also slips aren't a maneuver, there're a tool.
 
CTLSi said:
If you choose max flaps, you will find yourself almost hovering over the threshold before touch down. If you use standard flaps, you must have the skill to avoid stalling and using those wings to brake you at the exact right moment.
Click to expand...

I don't buy this at all. It's certainly not the case in the 150 he said he was flying. I learned in 152's and I was never EVER in any place close to stalling regardless of the flap setting. I have no clue what "standard" vs. "full" flaps are. As far as the FAA is concerned FULL=STANDARD. I've never "hovered" over the threshold either.
 
Jaybird180 said:
Henning I think the advice is misguided and could earn a checkride bust. DPEs want to see stable finals not chirping stall horns. After the ticket is earned, then practice lower edge of envelope stuff, but please do not do so at <pattern altitude. That's asking for a smoking hole in the ground from the weekend flyer; proficient pilot who flies often different story, different advice.
Click to expand...

This.... the PTS specifically says 1.3VSO (or published approach speed) +10/-5.

Additionally, I can't speak for the bush pilots, but I'd never consider intentionally putting the aircraft on the backside of the power curve that close to the ground. Wind shear, wake turbulence---there are too many things that can happen if your slow.

Judge the approach properly, slip if you need to, go around if you need to... much simpler. If your worried what your passengers will think, do what pilots have been doing since 1903---blame the wind.
 
flyingron said:
I don't buy this at all. It's certainly not the case in the 150 he said he was flying. I learned in 152's and I was never EVER in any place close to stalling regardless of the flap setting. I have no clue what "standard" vs. "full" flaps are. As far as the FAA is concerned FULL=STANDARD. I've never "hovered" over the threshold either.
Click to expand...

When I watch Cessna landings on YouTube I ALWAYS hear their little stall horn just before they touch down. A stall landing is done all the time. Especially on short fields.
 
Bonchie said:
Ok, but she still has to do it on her Checkride.
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Sure, and I pointed out the defect in the slip as well as how to avoid needing it.:D the key to learning to fly easily and well is Trim, Trim, Trim. Trim the correct speed in and the plane does virtually everything by its own nature, all you do is adjust throttle for vertical speed.
 
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I don't slip mine slow and heavy with 40 degrees of flaps. You can tail stall.

With the barn door flaps on mine, slips are almost extinct anyway. I just do one once in a while for fun.

Practice OP. Or as I like to say, "if you don't know what lever A does, lever B." ;)
 
Biggest mistake I see on this is people not recognizing that with a full-deflection slip, their airspeed indicator is pretty inaccurate, and you have to rely solely on pitch attitude to manage speed. As noted by others, sometimes folks have an overwhelming urge to push (you mothers know about that, right?) when trying a slip to a landing, perhaps because they're trying to get down and think that diving will help -- and it doesn't. Better to just leave the nose where it is and let the aerodynamics take care of themselves without burying the nose and gaining a lot of speed.
 
txflyer said:
I don't slip mine slow and heavy with 40 degrees of flaps. You can tail stall.
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I don't know of any production light single which will reach a tailplane stall before a wing stall in a slip -- even an older Cessna with 40 flap. From an aerodynamic standpoint, I'm not even sure how you'd do that unless you were outside the forward cg limit. Yes, on a 172 (and only a 172), it is possible to get into a bit of a pitch oscillation (not a flutter, not a tailplane stall) which can be instantly remedied by kicking out of the slip, but I've never experienced it despite a lot of slips with 40 flaps in 172's.
 
txflyer said:
I don't slip mine slow and heavy with 40 degrees of flaps. You can tail stall.



With the barn door flaps on mine, slips are almost extinct anyway. I just do one once in a while for fun.



Practice OP. Or as I like to say, "if you don't know what lever A does, lever B." ;)
Click to expand...


Take it up to altitude and try in a few different weight and balance configs to actually create a tail stall.

I have a feeling you'll find it nearly impossible in the real world in your aircraft.

It's not completely an OWT in Cessnas but the 172 placard warning against extended slips with flaps extended kinda encroached out to all Cessnas with no intent by the people who placarded the 172 to have it do so.

Certainly every airframe is different, so I say "go try it". See if you ever truly lose elevator authority in your aircraft. I seriously doubt you will. And you'll know more about your specific airplane.

Plus, it's fun. Take someone along who enjoys flying sideways. :)
 
O.k., I'll try to stall the **** out of the tail just for you guys. :goofy:

Remember me.
 
Ron Levy said:
I don't know of any production light single which will reach a tailplane stall before a wing stall in a slip -- even an older Cessna with 40 flap. From an aerodynamic standpoint, I'm not even sure how you'd do that unless you were outside the forward cg limit. Yes, on a 172 (and only a 172), it is possible to get into a bit of a pitch oscillation (not a flutter, not a tailplane stall) which can be instantly remedied by kicking out of the slip, but I've never experienced it despite a lot of slips with 40 flaps in 172's.
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It actually self corrects, that's why it oscillates. Yes, it goes away immediately with a bit of release of rudder, no, you don't have to, it's perfectly fine doing that.
 
txflyer said:
O.k., I'll try to stall the **** out of the tail just for you guys. :goofy:

Remember me.
Click to expand...

The effect isn't really a stall, you just put the tail in dirty air. I don't have the time in a 180 to say for sure, but I've never had it happen in a 182, skinny or fat, manual flaps or electric, and I use all the flaps, all the time.
 
I think it's in my POH not to slip with full flaps, but I'll have to confirm that.
 
txflyer said:
I think it's in my POH not to slip with full flaps, but I'll have to confirm that.
Click to expand...

The Normal Landing section of the Normal Procedures chapter of the Cessna 172N POH says this:

"Steep slips should be avoided with flap settings greater than 20° due to a tendency for the elevator to oscillate under certain combinations or airspeed, sideslip angle, and center of gravity loadings."​
Notice that it says "should," not "must," and it's not in the Limitations chapter, so it's a recommendation, not a prohibition.

I don't have a POH for the plane in your avatar.
 
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Hi Anna. You need to talk to your CFI. I think, based on your post, that you are flying the final too fast in a C-152 for a short field landing. You airspeed numbers sound more like a "normal" approach (if there is such a thing). For short field, you should have full flaps in. If you need to slip a little on final to land where you want to, then kick in just a little slip, then take it back out when your profile is where you want it. That is the beauty of a slip -- you can make minor adjustments in your profile to keep it like you want it.


Good luck on the check ride, and welcome to the Blue Board :)!
 
I see people have beaten this horse to death. My 2c is that I was in the same situations couple of years ago: slips just didn't work out so well. I don't recall what I did for DPE to complete the task, I think it was a perfunctory slip for imitation of off-field landing after engine failure. After that I avoided slipping. I got back to slips when I obtained my tailwheel endorsement. Not that tailwheel has anything with slips, but the airplane had no flaps, so I was slipping it often. Not sure if it's an option for OP.
 
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